Kim Dotcom is the founder of Megaupload, a now-defunct file-sharing online service that was registered in Hong Kong. The German citizen also has residency in New Zealand and Hong Kong. In January 2012, Dotcom was indicted in the US and accused of racketeering by facilitating massive copyright fraud. He was arrested in Coatesville, Auckland, New Zealand, during an armed raid and is fighting extradition to the US.

Kim Dotcom, accused of the biggest US copyright infringement as founder of file-sharing website Megaupload.com, won permission from a judge to sue New Zealand’s spy agency for intercepting his communications.

New Zealand High Court Justice Helen Winkelmann on Wednesday granted a request to add the Government Communications Security Bureau to Dotcom’s lawsuit against the country’s Attorney General over a January raid on his Auckland mansion.

“I have no doubt that the most convenient and expeditious way of enabling the court to determine all matters in dispute is to join the GCSB in the proceedings,” Winkelmann wrote in the 16-page ruling posted on the courts’ website on Thursday.

Dotcom, 38, was indicted in what US prosecutors dubbed a “Mega Conspiracy”, accusing his website of generating more than US$175 million in criminal proceeds from the exchange of pirated film, music, book and software files. He faces as long as 20 years in prison for each of the racketeering and money- laundering charges in the indictment, with the US seeking his extradition for a trial in Virginia.

New Zealand police raided Dotcom’s home using two helicopters and 27 officers, some armed with assault rifles and gas canisters. Police seized mobile phones, hard drives, computers and 18 luxury vehicles, including a 1959 pink Cadillac. Dotcom spent four weeks in jail before winning his release on bail.

Winkelmann ruled on June 28 that warrants police used to search Dotcom’s home were overly broad and invalid.

During an August hearing into whether the search itself was unreasonable and employed disproportionate force, the GCSB conceded it unlawfully intercepted Dotcom’s communications before the raid, Winkelmann wrote in the ruling.

“At least some of the material gathered by GCSB through the interceptions will be the subject of consideration in the proceeding in one form or another,” Winkelmann said. “There is a risk that the addition of the GCSB to this proceeding will delay the extradition proceeding, but in reality I think that is not a likely outcome.”